1. Technical Field
The present invention relates to a device for supplying constant number of parts, which counts predetermined necessary number (constant number or constant amount) of small parts such as bolt and nut existing in bulk (in random orientations and positions) and outputs the necessary number of small parts to a parts-output port located in a predetermined position.
2. Related Art
As this kind of device for supplying constant number of small parts, Patent Documents 1, 2 and 3 disclose the devices. In any of these prior art devices for supplying constant number of small parts, small parts such as bolt and nut are accommodated in bulk (in random orientations and positions) in a hopper, and a rotary disc embedded with magnets on a side surface of the rotary disc is set in the hopper. The rotary disc attracts one small parts by the magnet and raises it by rotation of the rotary disc while holding the one small parts by the magnet. The number of the small parts and a direction of the small parts are gradually limited by being made contact with a plurality of guide plates etc. that are provided in a rotation direction of the rotary disc. Then, each small parts is outputted to a predetermined conveyance line by being forcibly separated from the magnet by a final guide plate.
However, the prior art devices for supplying constant number of small parts disclosed in the Patent Documents 1, 2 and 3 are configured to output or take out one small parts, in principle, by one-time attraction of the small parts by the magnet and multi-time limitation and separation by the guide plates. Because of this, in order to certainly output one small parts, there is a need to repeat trial-and-error for determining shape and position of the guide plate etc. Further, in some cases, two small parts might be outputted at once. As a consequence, it takes long time to carry out the trial until facilities are formally launched. And also, there is still room for improvement in reliability of the output of the constant number of the small parts.